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  <section id="importing-modules">
<span id="importing"></span><h1>Importing Modules<a class="headerlink" href="#importing-modules" title="Permalink to this headline">¶</a></h1>
<dl class="function">
<dt id="c.PyImport_ImportModule">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ImportModule</code><span class="sig-paren">(</span>const char<em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportModule" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-0">This is a simplified interface to <a class="reference internal" href="#c.PyImport_ImportModuleEx" title="PyImport_ImportModuleEx"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportModuleEx()</span></code></a> below,
leaving the <em>globals</em> and <em>locals</em> arguments set to <code class="docutils literal notranslate"><span class="pre">NULL</span></code> and <em>level</em> set
to 0.  When the <em>name</em>
argument contains a dot (when it specifies a submodule of a package), the
<em>fromlist</em> argument is set to the list <code class="docutils literal notranslate"><span class="pre">['*']</span></code> so that the return value is the
named module rather than the top-level package containing it as would otherwise
be the case.  (Unfortunately, this has an additional side effect when <em>name</em> in
fact specifies a subpackage instead of a submodule: the submodules specified in
the package’s <code class="docutils literal notranslate"><span class="pre">__all__</span></code> variable are  loaded.)  Return a new reference to the
imported module, or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> with an exception set on failure.  A failing
import of a module doesn’t leave the module in <a class="reference internal" href="../library/sys.html#sys.modules" title="sys.modules"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.modules</span></code></a>.</p>
<p>This function always uses absolute imports.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ImportModuleNoBlock">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ImportModuleNoBlock</code><span class="sig-paren">(</span>const char<em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportModuleNoBlock" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>This function is a deprecated alias of <a class="reference internal" href="#c.PyImport_ImportModule" title="PyImport_ImportModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportModule()</span></code></a>.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.3: </span>This function used to fail immediately when the import lock was held
by another thread.  In Python 3.3 though, the locking scheme switched
to per-module locks for most purposes, so this function’s special
behaviour isn’t needed anymore.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ImportModuleEx">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ImportModuleEx</code><span class="sig-paren">(</span>const char<em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *globals</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *locals</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *fromlist</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportModuleEx" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-1">Import a module.  This is best described by referring to the built-in Python
function <a class="reference internal" href="../library/functions.html#__import__" title="__import__"><code class="xref py py-func docutils literal notranslate"><span class="pre">__import__()</span></code></a>.</p>
<p>The return value is a new reference to the imported module or top-level
package, or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> with an exception set on failure.  Like for
<a class="reference internal" href="../library/functions.html#__import__" title="__import__"><code class="xref py py-func docutils literal notranslate"><span class="pre">__import__()</span></code></a>, the return value when a submodule of a package was
requested is normally the top-level package, unless a non-empty <em>fromlist</em>
was given.</p>
<p>Failing imports remove incomplete module objects, like with
<a class="reference internal" href="#c.PyImport_ImportModule" title="PyImport_ImportModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportModule()</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ImportModuleLevelObject">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ImportModuleLevelObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *globals</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *locals</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *fromlist</em>, int<em> level</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportModuleLevelObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Import a module.  This is best described by referring to the built-in Python
function <a class="reference internal" href="../library/functions.html#__import__" title="__import__"><code class="xref py py-func docutils literal notranslate"><span class="pre">__import__()</span></code></a>, as the standard <a class="reference internal" href="../library/functions.html#__import__" title="__import__"><code class="xref py py-func docutils literal notranslate"><span class="pre">__import__()</span></code></a> function calls
this function directly.</p>
<p>The return value is a new reference to the imported module or top-level package,
or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> with an exception set on failure.  Like for <a class="reference internal" href="../library/functions.html#__import__" title="__import__"><code class="xref py py-func docutils literal notranslate"><span class="pre">__import__()</span></code></a>,
the return value when a submodule of a package was requested is normally the
top-level package, unless a non-empty <em>fromlist</em> was given.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.3.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ImportModuleLevel">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ImportModuleLevel</code><span class="sig-paren">(</span>const char<em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *globals</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *locals</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *fromlist</em>, int<em> level</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportModuleLevel" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Similar to <a class="reference internal" href="#c.PyImport_ImportModuleLevelObject" title="PyImport_ImportModuleLevelObject"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportModuleLevelObject()</span></code></a>, but the name is a
UTF-8 encoded string instead of a Unicode object.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.3: </span>Negative values for <em>level</em> are no longer accepted.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_Import">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_Import</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_Import" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>This is a higher-level interface that calls the current “import hook
function” (with an explicit <em>level</em> of 0, meaning absolute import).  It
invokes the <a class="reference internal" href="../library/functions.html#__import__" title="__import__"><code class="xref py py-func docutils literal notranslate"><span class="pre">__import__()</span></code></a> function from the <code class="docutils literal notranslate"><span class="pre">__builtins__</span></code> of the
current globals.  This means that the import is done using whatever import
hooks are installed in the current environment.</p>
<p>This function always uses absolute imports.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ReloadModule">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ReloadModule</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *m</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ReloadModule" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Reload a module.  Return a new reference to the reloaded module, or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> with
an exception set on failure (the module still exists in this case).</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_AddModuleObject">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_AddModuleObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_AddModuleObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>Return the module object corresponding to a module name.  The <em>name</em> argument
may be of the form <code class="docutils literal notranslate"><span class="pre">package.module</span></code>. First check the modules dictionary if
there’s one there, and if not, create a new one and insert it in the modules
dictionary. Return <code class="docutils literal notranslate"><span class="pre">NULL</span></code> with an exception set on failure.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>This function does not load or import the module; if the module wasn’t already
loaded, you will get an empty module object. Use <a class="reference internal" href="#c.PyImport_ImportModule" title="PyImport_ImportModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportModule()</span></code></a>
or one of its variants to import a module.  Package structures implied by a
dotted name for <em>name</em> are not created if not already present.</p>
</div>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.3.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_AddModule">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_AddModule</code><span class="sig-paren">(</span>const char<em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_AddModule" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>Similar to <a class="reference internal" href="#c.PyImport_AddModuleObject" title="PyImport_AddModuleObject"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_AddModuleObject()</span></code></a>, but the name is a UTF-8
encoded string instead of a Unicode object.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ExecCodeModule">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ExecCodeModule</code><span class="sig-paren">(</span>const char<em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *co</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ExecCodeModule" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-2">Given a module name (possibly of the form <code class="docutils literal notranslate"><span class="pre">package.module</span></code>) and a code object
read from a Python bytecode file or obtained from the built-in function
<a class="reference internal" href="../library/functions.html#compile" title="compile"><code class="xref py py-func docutils literal notranslate"><span class="pre">compile()</span></code></a>, load the module.  Return a new reference to the module object,
or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> with an exception set if an error occurred.  <em>name</em>
is removed from <a class="reference internal" href="../library/sys.html#sys.modules" title="sys.modules"><code class="xref py py-attr docutils literal notranslate"><span class="pre">sys.modules</span></code></a> in error cases, even if <em>name</em> was already
in <a class="reference internal" href="../library/sys.html#sys.modules" title="sys.modules"><code class="xref py py-attr docutils literal notranslate"><span class="pre">sys.modules</span></code></a> on entry to <a class="reference internal" href="#c.PyImport_ExecCodeModule" title="PyImport_ExecCodeModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModule()</span></code></a>.  Leaving
incompletely initialized modules in <a class="reference internal" href="../library/sys.html#sys.modules" title="sys.modules"><code class="xref py py-attr docutils literal notranslate"><span class="pre">sys.modules</span></code></a> is dangerous, as imports of
such modules have no way to know that the module object is an unknown (and
probably damaged with respect to the module author’s intents) state.</p>
<p>The module’s <a class="reference internal" href="../reference/import.html#__spec__" title="__spec__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__spec__</span></code></a> and <a class="reference internal" href="../reference/import.html#__loader__" title="__loader__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__loader__</span></code></a> will be set, if
not set already, with the appropriate values.  The spec’s loader will
be set to the module’s <code class="docutils literal notranslate"><span class="pre">__loader__</span></code> (if set) and to an instance of
<code class="xref py py-class docutils literal notranslate"><span class="pre">SourceFileLoader</span></code> otherwise.</p>
<p>The module’s <a class="reference internal" href="../reference/import.html#__file__" title="__file__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__file__</span></code></a> attribute will be set to the code object’s
<code class="xref c c-member docutils literal notranslate"><span class="pre">co_filename</span></code>.  If applicable, <a class="reference internal" href="../reference/import.html#__cached__" title="__cached__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__cached__</span></code></a> will also
be set.</p>
<p>This function will reload the module if it was already imported.  See
<a class="reference internal" href="#c.PyImport_ReloadModule" title="PyImport_ReloadModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ReloadModule()</span></code></a> for the intended way to reload a module.</p>
<p>If <em>name</em> points to a dotted name of the form <code class="docutils literal notranslate"><span class="pre">package.module</span></code>, any package
structures not already created will still not be created.</p>
<p>See also <a class="reference internal" href="#c.PyImport_ExecCodeModuleEx" title="PyImport_ExecCodeModuleEx"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModuleEx()</span></code></a> and
<a class="reference internal" href="#c.PyImport_ExecCodeModuleWithPathnames" title="PyImport_ExecCodeModuleWithPathnames"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModuleWithPathnames()</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ExecCodeModuleEx">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ExecCodeModuleEx</code><span class="sig-paren">(</span>const char<em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *co</em>, const char<em> *pathname</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ExecCodeModuleEx" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Like <a class="reference internal" href="#c.PyImport_ExecCodeModule" title="PyImport_ExecCodeModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModule()</span></code></a>, but the <a class="reference internal" href="../reference/import.html#__file__" title="__file__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__file__</span></code></a> attribute of
the module object is set to <em>pathname</em> if it is non-<code class="docutils literal notranslate"><span class="pre">NULL</span></code>.</p>
<p>See also <a class="reference internal" href="#c.PyImport_ExecCodeModuleWithPathnames" title="PyImport_ExecCodeModuleWithPathnames"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModuleWithPathnames()</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ExecCodeModuleObject">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ExecCodeModuleObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *co</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *pathname</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *cpathname</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ExecCodeModuleObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Like <a class="reference internal" href="#c.PyImport_ExecCodeModuleEx" title="PyImport_ExecCodeModuleEx"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModuleEx()</span></code></a>, but the <a class="reference internal" href="../reference/import.html#__cached__" title="__cached__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__cached__</span></code></a>
attribute of the module object is set to <em>cpathname</em> if it is
non-<code class="docutils literal notranslate"><span class="pre">NULL</span></code>.  Of the three functions, this is the preferred one to use.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.3.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ExecCodeModuleWithPathnames">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_ExecCodeModuleWithPathnames</code><span class="sig-paren">(</span>const char<em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *co</em>, const char<em> *pathname</em>, const char<em> *cpathname</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ExecCodeModuleWithPathnames" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Like <a class="reference internal" href="#c.PyImport_ExecCodeModuleObject" title="PyImport_ExecCodeModuleObject"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExecCodeModuleObject()</span></code></a>, but <em>name</em>, <em>pathname</em> and
<em>cpathname</em> are UTF-8 encoded strings. Attempts are also made to figure out
what the value for <em>pathname</em> should be from <em>cpathname</em> if the former is
set to <code class="docutils literal notranslate"><span class="pre">NULL</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.2.</span></p>
</div>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.3: </span>Uses <a class="reference internal" href="../library/imp.html#imp.source_from_cache" title="imp.source_from_cache"><code class="xref py py-func docutils literal notranslate"><span class="pre">imp.source_from_cache()</span></code></a> in calculating the source path if
only the bytecode path is provided.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_GetMagicNumber">
long <code class="sig-name descname">PyImport_GetMagicNumber</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_GetMagicNumber" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the magic number for Python bytecode files (a.k.a. <code class="file docutils literal notranslate"><span class="pre">.pyc</span></code> file).
The magic number should be present in the first four bytes of the bytecode
file, in little-endian byte order. Returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> on error.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.3: </span>Return value of <code class="docutils literal notranslate"><span class="pre">-1</span></code> upon failure.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_GetMagicTag">
const char * <code class="sig-name descname">PyImport_GetMagicTag</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_GetMagicTag" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the magic tag string for <span class="target" id="index-3"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-3147"><strong>PEP 3147</strong></a> format Python bytecode file
names.  Keep in mind that the value at <code class="docutils literal notranslate"><span class="pre">sys.implementation.cache_tag</span></code> is
authoritative and should be used instead of this function.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.2.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_GetModuleDict">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_GetModuleDict</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_GetModuleDict" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: Borrowed reference.</em><p>Return the dictionary used for the module administration (a.k.a.
<code class="docutils literal notranslate"><span class="pre">sys.modules</span></code>).  Note that this is a per-interpreter variable.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_GetModule">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_GetModule</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_GetModule" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Return the already imported module with the given name.  If the
module has not been imported yet then returns <code class="docutils literal notranslate"><span class="pre">NULL</span></code> but does not set
an error.  Returns <code class="docutils literal notranslate"><span class="pre">NULL</span></code> and sets an error if the lookup failed.</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.7.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_GetImporter">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="sig-name descname">PyImport_GetImporter</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *path</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_GetImporter" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Return a finder object for a <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a>/<code class="xref py py-attr docutils literal notranslate"><span class="pre">pkg.__path__</span></code> item
<em>path</em>, possibly by fetching it from the <a class="reference internal" href="../library/sys.html#sys.path_importer_cache" title="sys.path_importer_cache"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path_importer_cache</span></code></a>
dict.  If it wasn’t yet cached, traverse <a class="reference internal" href="../library/sys.html#sys.path_hooks" title="sys.path_hooks"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path_hooks</span></code></a> until a hook
is found that can handle the path item.  Return <code class="docutils literal notranslate"><span class="pre">None</span></code> if no hook could;
this tells our caller that the <a class="reference internal" href="../glossary.html#term-path-based-finder"><span class="xref std std-term">path based finder</span></a> could not find a
finder for this path item. Cache the result in <a class="reference internal" href="../library/sys.html#sys.path_importer_cache" title="sys.path_importer_cache"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path_importer_cache</span></code></a>.
Return a new reference to the finder object.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ImportFrozenModuleObject">
int <code class="sig-name descname">PyImport_ImportFrozenModuleObject</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportFrozenModuleObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Load a frozen module named <em>name</em>.  Return <code class="docutils literal notranslate"><span class="pre">1</span></code> for success, <code class="docutils literal notranslate"><span class="pre">0</span></code> if the
module is not found, and <code class="docutils literal notranslate"><span class="pre">-1</span></code> with an exception set if the initialization
failed.  To access the imported module on a successful load, use
<a class="reference internal" href="#c.PyImport_ImportModule" title="PyImport_ImportModule"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportModule()</span></code></a>.  (Note the misnomer — this function would
reload the module if it was already imported.)</p>
<div class="versionadded">
<p><span class="versionmodified added">New in version 3.3.</span></p>
</div>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.4: </span>The <code class="docutils literal notranslate"><span class="pre">__file__</span></code> attribute is no longer set on the module.</p>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ImportFrozenModule">
int <code class="sig-name descname">PyImport_ImportFrozenModule</code><span class="sig-paren">(</span>const char<em> *name</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ImportFrozenModule" title="Permalink to this definition">¶</a></dt>
<dd><p>Similar to <a class="reference internal" href="#c.PyImport_ImportFrozenModuleObject" title="PyImport_ImportFrozenModuleObject"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ImportFrozenModuleObject()</span></code></a>, but the name is a
UTF-8 encoded string instead of a Unicode object.</p>
</dd></dl>

<dl class="type">
<dt id="c._frozen">
struct <code class="sig-name descname">_frozen</code><a class="headerlink" href="#c._frozen" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-4">This is the structure type definition for frozen module descriptors, as
generated by the <strong class="program">freeze</strong> utility (see <code class="file docutils literal notranslate"><span class="pre">Tools/freeze/</span></code> in the
Python source distribution).  Its definition, found in <code class="file docutils literal notranslate"><span class="pre">Include/import.h</span></code>,
is:</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="k">struct</span> <span class="nc">_frozen</span> <span class="p">{</span>
    <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">name</span><span class="p">;</span>
    <span class="k">const</span> <span class="kt">unsigned</span> <span class="kt">char</span> <span class="o">*</span><span class="n">code</span><span class="p">;</span>
    <span class="kt">int</span> <span class="n">size</span><span class="p">;</span>
<span class="p">};</span>
</pre></div>
</div>
</dd></dl>

<dl class="var">
<dt id="c.PyImport_FrozenModules">
const struct <a class="reference internal" href="#c._frozen" title="_frozen">_frozen</a>* <code class="sig-name descname">PyImport_FrozenModules</code><a class="headerlink" href="#c.PyImport_FrozenModules" title="Permalink to this definition">¶</a></dt>
<dd><p>This pointer is initialized to point to an array of <code class="xref c c-type docutils literal notranslate"><span class="pre">struct</span> <span class="pre">_frozen</span></code>
records, terminated by one whose members are all <code class="docutils literal notranslate"><span class="pre">NULL</span></code> or zero.  When a frozen
module is imported, it is searched in this table.  Third-party code could play
tricks with this to provide a dynamically created collection of frozen modules.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_AppendInittab">
int <code class="sig-name descname">PyImport_AppendInittab</code><span class="sig-paren">(</span>const char<em> *name</em>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* (<em>*initfunc</em>)(void)<span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_AppendInittab" title="Permalink to this definition">¶</a></dt>
<dd><p>Add a single module to the existing table of built-in modules.  This is a
convenience wrapper around <a class="reference internal" href="#c.PyImport_ExtendInittab" title="PyImport_ExtendInittab"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExtendInittab()</span></code></a>, returning <code class="docutils literal notranslate"><span class="pre">-1</span></code> if
the table could not be extended.  The new module can be imported by the name
<em>name</em>, and uses the function <em>initfunc</em> as the initialization function called
on the first attempted import.  This should be called before
<a class="reference internal" href="init.html#c.Py_Initialize" title="Py_Initialize"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_Initialize()</span></code></a>.</p>
</dd></dl>

<dl class="type">
<dt id="c._inittab">
struct <code class="sig-name descname">_inittab</code><a class="headerlink" href="#c._inittab" title="Permalink to this definition">¶</a></dt>
<dd><p>Structure describing a single entry in the list of built-in modules.  Each of
these structures gives the name and initialization function for a module built
into the interpreter.  The name is an ASCII encoded string.  Programs which
embed Python may use an array of these structures in conjunction with
<a class="reference internal" href="#c.PyImport_ExtendInittab" title="PyImport_ExtendInittab"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExtendInittab()</span></code></a> to provide additional built-in modules.
The structure is defined in <code class="file docutils literal notranslate"><span class="pre">Include/import.h</span></code> as:</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="k">struct</span> <span class="nc">_inittab</span> <span class="p">{</span>
    <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span><span class="n">name</span><span class="p">;</span>           <span class="cm">/* ASCII encoded string */</span>
    <span class="n">PyObject</span><span class="o">*</span> <span class="p">(</span><span class="o">*</span><span class="n">initfunc</span><span class="p">)(</span><span class="kt">void</span><span class="p">);</span>
<span class="p">};</span>
</pre></div>
</div>
</dd></dl>

<dl class="function">
<dt id="c.PyImport_ExtendInittab">
int <code class="sig-name descname">PyImport_ExtendInittab</code><span class="sig-paren">(</span>struct <a class="reference internal" href="#c._inittab" title="_inittab">_inittab</a><em> *newtab</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyImport_ExtendInittab" title="Permalink to this definition">¶</a></dt>
<dd><p>Add a collection of modules to the table of built-in modules.  The <em>newtab</em>
array must end with a sentinel entry which contains <code class="docutils literal notranslate"><span class="pre">NULL</span></code> for the <code class="xref py py-attr docutils literal notranslate"><span class="pre">name</span></code>
field; failure to provide the sentinel value can result in a memory fault.
Returns <code class="docutils literal notranslate"><span class="pre">0</span></code> on success or <code class="docutils literal notranslate"><span class="pre">-1</span></code> if insufficient memory could be allocated to
extend the internal table.  In the event of failure, no modules are added to the
internal table.  This must be called before <a class="reference internal" href="init.html#c.Py_Initialize" title="Py_Initialize"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_Initialize()</span></code></a>.</p>
<p>If Python is initialized multiple times, <a class="reference internal" href="#c.PyImport_AppendInittab" title="PyImport_AppendInittab"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_AppendInittab()</span></code></a> or
<a class="reference internal" href="#c.PyImport_ExtendInittab" title="PyImport_ExtendInittab"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyImport_ExtendInittab()</span></code></a> must be called before each Python
initialization.</p>
</dd></dl>

</section>


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